<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<style>
    ul li{
        width: 100px;
        height: 30px;
        border: 1px solid grey;
        list-style: none;
        float: left;
        text-align: center;
        line-height: 30px;
    }
    .active{
        background-color: #00b3ee;
    }
</style>
<body>
<ul>
    <li class="active">home</li>
    <li>nav</li>
    <li>about</li>
    <li>aaaa</li>
    <li>bbbbb</li>
</ul>
<script src="jquery-2.1.1.js"></script>
<script>
    $("ul>li").click(function () {
        $("ul>li").removeClass("active");
        $(this).addClass("active");
    })
</script>
</body>
</html>